Comparative Analysis of Evapotranspiration in Typical Grassland Areas Based on Remote Sensing and Hydrological Models
Based on the measured monthly runoff sequence data of hydrological stations in the Xilin River basin,the Nash efficiency coefficient(Ens)and determination coefficient(R2)were used as evaluation indexes to verify the applica-bility of APEX model in hydrological simulation.The evaporation results of the SEBAL model and the MOD16 A2 data were analyzed,and the accuracy was verified by using the Penman-Monteith formula in the APEX model.The monthly average evapotranspiration of APEX model was compared with the SEBAL model and MOD16 A2.The results show that for the measured runoff and simulation by the APEX model,Ens=0.63 and R2=0.66 in calibration period while in veri-fication period,Ens=0.62,R2=0.66;For the daily evapotranspiration calculation results by the Penman-Monteith for-mula in the SEBAL model and the APEX model,Ens=0.68,R2=0.80 while Ens=0.71,R2=0.85 for monthly evapo-transpiration results;For the monthly evaporation results by MOD16 A2 data and the Penman-Monteith formula,Ens=0.58,R2=0.78;The average monthly evapotranspiration of MOD16 A2 data at the watershed scale in the same period is maximum.The results can provide support for evapotranspiration estimation in grassland basins.
万方数据
维普
